When someone is confronted with a diagnosis of cancer, in the vast majority of cases doctors recommend surgery — often, as quickly as possible. The goal is to remove the cancer, with the hope that the person can go on to live a normal, cancer-free life. But unfortunately, the reality is often otherwise. For far too many people, cancer recurs; either at the primary site, or the cancer metastasizes, arising at sites distant from where the cancer originated, often in life-threatening areas, such as the lung, liver, brain, or bone.